Targeting inhibition of extracellular signal-regulated kinase kinase pathway with AZD6244 (ARRY-142886) suppresses growth and angiogenesis of gastric cancer

Identification and validation VAT1 in gastric cancer through bioinformatics and experimental analysis

This study investigated the expression pattern of Vesicular Amine Transporter 1 (VAT1) in gastric cancer (GC) and its impact on prognosis, alongside evaluating its potential as a biomarker for immunotherapy and chemotherapy. Analysis of transcriptomic data, supported by experimental validation, revealed that VAT1 is highly expressed in GC and is associated with poor prognosis. Kaplan-Meier and ROC analyses demonstrated VAT1's potential in GC diagnosis, while multivariate analysis confirmed its role as an independent risk factor. Gene set enrichment analysis indicated that VAT1 plays a role in regulating the MAPK signaling pathway and epithelial-mesenchymal transition (EMT) in GC. Immune infiltration analysis showed a positive correlation between VAT1 and immune cells, particularly macrophages, and a negative correlation with chemotherapy sensitivity. In vitro and in vivo experiments further confirmed VAT1's critical role in promoting GC cell proliferation and inhibiting apoptosis. Overall, VAT1 holds significant value not only in GC diagnosis and prognosis but also as a potential target for immunotherapy and overcoming drug resistance.

Multi-omics-driven discovery of invasive patterns and treatment strategies in CA19-9 positive intrahepatic cholangiocarcinoma

BACKGROUND

Intrahepatic cholangiocarcinoma (ICC) is a malignant tumor with a poor prognosis, predominantly CA19-9 positive. High CA19-9 levels correlate with increased aggressiveness and worse outcomes. This study employs multi-omics analysis to reveal molecular features and identify therapeutic targets of CA19-9 positive ICC, aiming to support individualized treatment.

METHODS

Data from seven clinical cohorts, two whole-exome sequencing cohorts, six RNA sequencing/microarray cohorts, one proteomic cohort, 20 single-cell RNA sequencing samples, and one spatial transcriptome sample were analyzed. Key findings were validated on tissue microarrays from 52 ICC samples.

RESULTS

CA19-9 positive ICC exhibited poorer OS (median 24.1 v.s. 51.5 months) and RFS (median 11.7 v.s. 28.2 months) compared to negative group (all P < 0.05). Genomic analysis revealed a higher KRAS mutation frequency in the positive group and a greater prevalence of IDH1/2 mutations in the negative group (all P < 0.05). Transcriptomic analysis indicated upregulated glycolysis pathways in CA19-9 positive ICC. Single-cell analysis identified specific glycolysis-related cell subclusters associated with poor prognosis, including Epi_SLC2A1, CAF_VEGFA, and Mph_SPP1. Higher hypoxia in the CA19-9 positive group led to metabolic reprogramming and promoted these cells' formation. These cells formed interactive communities promoting epithelial-mesenchymal transition (EMT) and angiogenesis. Drug sensitivity analysis identified six potential therapeutic drugs.

CONCLUSIONS

This study systematically elucidated the clinical, genomic, transcriptomic, and immune features of CA19-9 positive ICC. It reveals glycolysis-associated cellular communities and their cancer-promoting mechanisms, enhancing our understanding of ICC and laying the groundwork for individualized therapeutic strategies.

Natural products and derivatives for breast cancer treatment: From drug discovery to molecular mechanism

BACKGROUND

Breast cancer stands as the most common malignancy among women globally and a leading cause of cancer-related mortality. Conventional treatments, such as surgery, hormone therapy, radiotherapy, chemotherapy, and small-molecule targeted therapy, often fall short of addressing the complexity and heterogeneity of certain breast cancer subtypes, leading to drug resistance and metastatic progression. Thus, the search for novel therapeutic targets and agents is imperative. Given their low toxicity and abundant variety, natural products and their derivatives are increasingly considered valuable sources for small-molecule anticancer drugs.

PURPOSE

This review aims to elucidate the pharmacological impacts and underlying mechanisms of active compounds found in select natural products and their derivatives, primarily focusing on breast cancer treatment. It intends to underscore the potential of these substances in combating breast cancer and guide future research directions for the development of natural product-based therapeutics.

METHODS

We conducted comprehensive searches in electronic databases such as PubMed, Web of Science, and Scopus until October 2023, using keywords such as 'breast cancer', 'natural products', 'derivatives', 'mechanism', 'signaling pathways', and various keyword combinations.

RESULTS

The review presents a spectrum of phytochemicals, including but not limited to flavonoids, polyphenols, and alkaloids, and examines their actions in various animal and cellular models of breast cancer. The anticancer effects of these natural products and derivatives are manifested through diverse mechanisms, including induction of cell death via apoptosis and autophagy, and suppression of tumor angiogenesis.

CONCLUSION

An increasing array of natural products and their derivatives are proving effective against breast cancer. Future therapeutic strategies can benefit from strategic enhancement of the anticancer properties of natural compounds, optimization for targeted action, improved bioavailability, and minimized side effects. The forthcoming research on natural products should prioritize these facets to maximize their therapeutic potential.

In ovo injection of AZD6244 suppresses feather follicle development by the inhibition of ERK and Wnt/β-catenin pathways in goose embryos (Anser cygnoides)

1. Feathers are an important product from poultry, and the state of feather growth and development plays an important role in their economic value.2. In total, 120 eggs were selected for immunoblotting and immunolocalisation experiments of ERK and β-catenin proteins in different developmental stages of goose embryos. The ERK protein was highly expressed in the early stage of goose embryo development, while β-catenin protein was highly expressed in the middle stage of embryo development.3. The 120 eggs were divided into four treatment groups, including an uninjected group (BLANK), a group injected with 100 µl of cosolvent (CK), a group injected with 100 µl of AZD6244 containing cosolvent in a dose of 5 mg/kg AZD6244 containing cosolvent (AZD5) and a group injected with 100 µl of AZD6244 containing cosolvent in a dose of 15 mg/kg AZD6244 containing cosolvent (AZD15). The eggs were injected on the ninth day of embryonic development (E9). Samples were collected at E21.5 to observe feather width, feather follicle diameter, ERK and Wnt/β-catenin pathway protein expression.4. The AZD5 and AZD15 doses were within the embryonic safety range compared to the BLANK and CK groups and had no significant effect on the survival rate and weight at the inflection point, but significantly reduced the feather width and feather follicle diameter (p < 0.05). The AZD6244 treatment inhibited ERK protein phosphorylation levels and blocked the Wnt/β-catenin pathway, which in turn significantly down-regulated the expression levels of FZD4, β-catenin, TCF4 and LEF1 (p < 0.05), with an inhibitory effect in the AZD15 group being more significant. The immunohistochemical results of β-catenin and p-ERK were consistent with Western blot results.5. The small molecule inhibitor AZD6244 regulated the growth and development of feather follicles in goose embryos by the ERK and Wnt/β-catenin pathways.

Benzimidazole and its derivatives as cancer therapeutics: The potential role from traditional to precision medicine

Cancer is the second leading cause of mortality globally which remains a continuing threat to human health today. Drug insensitivity and resistance are critical hurdles in cancer treatment; therefore, the development of new entities targeting malignant cells is considered a high priority. Targeted therapy is the cornerstone of precision medicine. The synthesis of benzimidazole has garnered the attention of medicinal chemists and biologists due to its remarkable medicinal and pharmacological properties. Benzimidazole has a heterocyclic pharmacophore, which is an essential scaffold in drug and pharmaceutical development. Multiple studies have demonstrated the bioactivities of benzimidazole and its derivatives as potential anticancer therapeutics, either through targeting specific molecules or non-gene-specific strategies. This review provides an update on the mechanism of actions of various benzimidazole derivatives and the structure‒activity relationship from conventional anticancer to precision healthcare and from bench to clinics.

Molecular mechanisms underlying the action of carcinogens in gastric cancer with a glimpse into targeted therapy

BACKGROUND

Gastric cancer imposes a substantial global health burden despite its overall incidence decrease. A broad spectrum of inherited, environmental and infectious factors contributes to the development of gastric cancer. A profound understanding of the molecular underpinnings of gastric cancer has lagged compared to several other tumors with similar incidence and morbidity rates, owing to our limited knowledge of the role of carcinogens in this malignancy. The International Agency for Research on Cancer (IARC) has classified gastric carcinogenic agents into four groups based on scientific evidence from human and experimental animal studies. This review aims to explore the potential comprehensive molecular and biological impacts of carcinogens on gastric cancer development and their interactions and interferences with various cellular signaling pathways.

CONCLUSIONS

In this review, we highlight recent clinical trial data reported in the literature dealing with different ways to target various carcinogens in gastric cancer. Moreover, we touch upon other multidisciplinary therapeutic approaches such as surgery, adjuvant and neoadjuvant chemotherapy. Rational clinical trials focusing on identifying suitable patient populations are imperative to the success of single-agent therapeutics. Novel insights regarding signaling pathways that regulate gastric cancer can potentially improve treatment responses to targeted therapy alone or in combination with other/conventional treatments. Preventive strategies such as control of H. pylori infection through eradication or immunization as well as dietary habit and lifestyle changes may reduce the incidence of this multifactorial disease, especially in high prevalence areas. Further in-depth understanding of the molecular mechanisms involved in the role of carcinogenic agents in gastric cancer development may offer valuable information and update state-of-the-art resources for physicians and researchers to explore novel ways to combat this disease, from bench to bedside. A schematic outlining of the interaction between gastric carcinogenic agents and intracellular pathways in gastric cancer H. pylori stimulates multiple intracellular pathways, including PI3K/AKT, NF-κB, Wnt, Shh, Ras/Raf, c-MET, and JAK/STAT, leading to epithelial cell proliferation and differentiation, apoptosis, survival, motility, and inflammatory cytokine release. EBV can stimulate intracellular pathways such as the PI3K/Akt, RAS/RAF, JAK/STAT, Notch, TGF-β, and NF-κB, leading to cell survival and motility, proliferation, invasion, metastasis, and the transcription of anti-apoptotic genes and pro-inflammatory cytokines. Nicotine and alcohol can lead to angiogenesis, metastasis, survival, proliferation, pro-inflammatory, migration, and chemotactic by stimulating various intracellular signaling pathways such as PI3K/AKT, NF-κB, Ras/Raf, ROS, and JAK/STAT. Processed meat contains numerous carcinogenic compounds that affect multiple intracellular pathways such as sGC/cGMP, p38 MAPK, ERK, and PI3K/AKT, leading to anti-apoptosis, angiogenesis, metastasis, inflammatory responses, proliferation, and invasion. Lead compounds may interact with multiple signaling pathways such as PI3K/AKT, NF-κB, Ras/Raf, DNA methylation-dependent, and epigenetic-dependent, leading to tumorigenesis, carcinogenesis, malignancy, angiogenesis, DNA hypermethylation, cell survival, and cell proliferation. Stimulating signaling pathways such as PI3K/Akt, RAS/RAF, JAK/STAT, WNT, TGF-β, EGF, FGFR2, and E-cadherin through UV ionizing radiation leads to cell survival, proliferation, and immortalization in gastric cancer. The consequence of PI3K/AKT, NF-κB, Ras/Raf, ROS, JAK/STAT, and WNT signaling stimulation by the carcinogenic component of Pickled vegetables and salted fish is the Warburg effect, tumorigenesis, angiogenesis, proliferation, inflammatory response, and migration.

The Role of Bioactive Compounds in Natural Products Extracted from Plants in Cancer Treatment and Their Mechanisms Related to Anticancer Effects

Cancer is one of the greatest causes of death worldwide. With the development of surgery, radiotherapy, and medical agents, the outcomes of cancer patients have greatly improved. However, the underlying mechanisms of cancer are not yet fully understood. Recently, natural products have been proven to be beneficial for various conditions and have played important roles in the development of novel therapies. A substantial amount of evidence indicates that bioactive compounds could improve the outcomes of cancer patients via various pathways, such as endoplasmic reticulum stress, epigenetic modification, and modulation of oxidative stress. Here, we review the current evidence of bioactive compounds in natural products for the treatment of cancer and summarize the underlying mechanisms in this pathological process.

Molecular and Biological Mechanisms Underlying Gender Differences in COVID-19 Severity and Mortality

Globally, over two million people have perished due to the recent pandemic caused by SARS-CoV-2. The available epidemiological global data for SARS-CoV-2 portrays a higher rate of severity and mortality in males. Analyzing gender differences in the host mechanisms involved in SARS-CoV-2 infection and progression may offer insight into the more detrimental disease prognosis and clinical outcome in males. Therefore, we outline sexual dimorphisms which exist in particular host factors and elaborate on how they may contribute to the pronounced severity in male COVID-19 patients. This includes disparities detected in comorbidities, the ACE2 receptor, renin-angiotensin system (RAS), signaling molecules involved in SARS-CoV-2 replication, proteases which prime viral S protein, the immune response, and behavioral considerations. Moreover, we discuss sexual disparities associated with other viruses and a possible gender-dependent response to SARS-CoV-2 vaccines. By specifically highlighting these immune-endocrine processes as well as behavioral factors that differentially exist between the genders, we aim to offer a better understanding in the variations of SARS-CoV-2 pathogenicity.

Treatment Strategies of Gastric Cancer-Molecular Targets for Anti-angiogenic Therapy: a State-of-the-art Review

Purpose

Recent studies have suggested that molecular targets for the anti-angiogenic therapy might constitute a basis for additional therapy in gastric cancer treatment. A vast number of molecules, receptors, pathways, specific interactions, and thus strategies that target gastric cancer angiogenesis specifically have been reported in numerous research articles and clinical trials.

Methods

We conducted a systematic literature review of molecularly targeted treatment strategies in gastric cancer on the following databases—PubMed, Google Scholar, and Scopus—on September 20, 2020. Multiple articles and evaluations were searched for studies reporting newly found and promising molecular anti-angiogenic therapy pathways. Eventually, 39 articles regarding the anti-angiogenic therapy in gastric cancer were included in the final analysis.

Results

As a consequence of the release of the pro-angiogenic molecules from the tumour cells, gastric cancer presents high angiogenic capability. Therefore, potential schemes for future treatment strategies include the decrease of the process ligands as well as the expression of their receptors. Moreover, the increase in the angiogenic inhibitor levels and direct aim for the inner walls of the endothelial cells appear as a promising therapeutic strategy. Beyond that, angiogenesis process inhibition seems to indirectly exaggerate the effects of chemotherapy in the considered patients.

Conclusions

The anti-angiogenic treatment in gastric cancer patients evaluates its significance especially in the early stages of the malignancy. The studies conducted so far show that most of the meaningful angiogenic factors and receptors with the potential molecular pathways should be further evaluated since they could potentially play a substantial role in future therapies.

miRNA-Mediated Suppression of a Cardioprotective Cardiokine as a Novel Mechanism Exacerbating Post-MI Remodeling by Sleep Breathing Disorders

Rationale:

Obstructive sleep apnea-hypopnea syndrome, a sleep breathing disorder in which chronic intermittent hypoxia (CIH) is the primary pathology, is associated with multiple cardiovascular diseases. However, whether and how CIH may affect cardiac remodeling following myocardial infarction (MI) remains unknown.

Objective:

To determine whether CIH exposure at different periods of MI may exacerbate post-MI heart failure and to identify the mechanisms underlying CIH-exacerbated post-MI remodeling.

Methods and Results:

Adult male mice were subjected to MI (4 weeks) with and without CIH (4 or 8 weeks). CIH before MI (CIH+MI) had no significant effect on post-MI remodeling. However, double CIH exposure (CIH+MI+CIH) or CIH only during the MI period (MI+CIH) significantly exacerbated pathological remodeling and reduced survival rate. Mechanistically, CIH activated TGF-β (tumor growth factor-β)/Smad (homologs of both the Drosophila protein MAD and the C. elegans protein SMA) signaling and enhanced cardiac epithelial to mesenchymal transition, markedly increasing post-MI cardiac fibrosis. Transcriptome analysis revealed that, among 15 genes significantly downregulated (MI+CIH versus MI), Ctrp9 (a novel cardioprotective cardiokine) was one of the most significantly inhibited genes. Real-time polymerase chain reaction/Western analysis confirmed that cardiomyocyte CTRP9 expression was significantly reduced in MI+CIH mice. RNA-sequencing, real-time polymerase chain reaction, and dual-luciferase reporter assays identified that microRNA-214-3p is a novel Ctrp9 targeting miRNA. Its upregulation is responsible for Ctrp9 gene suppression in MI+CIH. Finally, AAV9 (adeno-associated virus 9)-mediated cardiac-specific CTRP9 overexpression or rCTRP9 (recombinated CTRP9) administration inhibited TGF-β/Smad and Wnt/β-catenin pathways, attenuated interstitial fibrosis, improved cardiac function, and enhanced survival rate in MI+CIH animals.

Conclusions:

This study provides the first evidence that MI+CIH upregulates miR-214-3p, suppresses cardiac CTRP9 (C1q tumor necrosis factor-related protein-9) expression, and exacerbates cardiac remodeling, suggesting that CTRP9 may be a novel therapeutic target against pathological remodeling in MI patients with obstructive sleep apnea-hypopnea syndrome.

Phytochemicals for the Prevention and Treatment of Gastric Cancer: Effects and Mechanisms

Gastric cancer is the fifth most common cancer, and the third most prevalent cause of cancer-related deaths in the world. Voluminous evidence has demonstrated that phytochemicals play a critical role in the prevention and management of gastric cancer. Most epidemiological investigations indicate that the increased intake of phytochemicals could reduce the risk of gastric cancer. Experimental studies have elucidated the mechanisms of action, including inhibiting cancer cell proliferation, inducing apoptosis and autophagy, and suppressing angiogenesis as well as cancer cell metastasis. These mechanisms have also been related to the inhibition of Helicobacter pylori and the modulation of gut microbiota. In addition, the intake of phytochemicals could enhance the efficacy of anticancer chemotherapeutics. Moreover, clinical studies have illustrated that phytochemicals have the potential for the prevention and the management of gastric cancer in humans. To provide an updated understanding of relationships between phytochemicals and gastric cancer, this review summarizes the effects of phytochemicals on gastric cancer, highlighting the underlying mechanisms. This review could be helpful for guiding the public in preventing gastric cancer through phytochemicals, as well as in developing functional food and drugs for the prevention and treatment of gastric cancer.

Suppressing growth and invasion of human hepatocellular carcinoma cells by celecoxib through inhibition of cyclooxygenase-2

Purpose: Biomarkers are lacking in hepatocellular carcinoma (HCC). Cyclooxygenase-2 (COX-2) and its metabolites play crucial roles in the process of inflammation-tumor transformation. This study was aimed to detect COX-2 expression in HCC tissues and evaluate the effects of a COX-2 inhibitor, celecoxib, on biological behaviors of HCC cell lines in vitro.

Methods: COX-2 expression was detected by immunohistochemistry on a human HCC tissue microarray. The correlations of COX-2 expression with tumor clinicopathological variables and overall survival were analyzed. The proliferation, apoptosis, cell cycle distribution, invasion capacity, and related signaling molecules of HCC cells after incubated with COX-2 inhibitor celecoxib were evaluated in vitro.

Results: Expression levels of COX-2 in HCC tissues were significantly higher than those in paracancerous tissues. The TNM stage III-IV, tumor size >5 cm, lymphovascular invasion and distant metastasis was higher in high COX-2 expression group compared with that in low COX-2 expression group. Patients with low COX-2 expression achieved better 5-year overall survival than those with high COX-2 expression. Treatment with celecoxib was sufficient to inhibit cell proliferation, promote apoptosis, and induce G0/G1 cell cycle arrest in HCC cells with concentration- and time-dependent manners. Celecoxib up-regulated E-cadherin protein through inhibiting COX-2-prostaglandin E2 (PGE2)-PGE2 receptor 2 (EP2)-p-Akt/p-ERK signaling pathway to suppress HCC cells migration and invasion.

Conclusion: High COX-2 expression was associated with advanced TNM stage, larger tumor size, increased lymphovascular invasion and short survival. Targeting inhibition of COX-2 by celecoxib exhibited anti-tumor activities by suppressing proliferation, promoting apoptosis, and inhibiting the aggressive properties of HCC cells.

High HIF-1α expression predicts poor prognosis of patients with colon adenocarcinoma

Hypoxia inducible factor 1 alpha subunit (HIF-1α) is induced in hypoxic conditions and plays a crucial role in the neoangiogenesis and metastasis of cancer. In this study, we aimed to evaluate the expression of HIF-1α in colon adenocarcinoma and to explore its clinicopathological characteristics and prognosis. A tissue microarray involving colon adenocarcinoma tissues and their corresponding paracancerous tissues from 92 patients was utilized to detect HIF-1α. The expression of HIF-1α in colon adenocarcinoma tissues was significantly higher than it was in the corresponding paracancerous tissues (P < 0.001). Furthermore, similar results were observed in HCT116 and RKO human colon adenocarcinoma xenografts in node mice (P < 0.05). Additionally, augmented HIF-1α expression was positively associated with TNM stage III-IV (P = 0.025), the presence of distant metastasis and vascular invasion (P = 0.048), and the presence of positive lymph nodes (P = 0.041). A Kaplan-Meier survival analysis showed that up-regulation of HIF-1α was associated with poor 5-year or 10-year survival (P < 0.05). A multivariable Cox regression analysis also found HIF-1α was an independent risk factor for poor prognosis in colon adenocarcinoma. Thus, targeting HIF-1α might be a viable strategy to treat patients with colon adenocarcinoma.

High-Density Infiltration of V-domain Immunoglobulin Suppressor of T-cell Activation Up-regulated Immune Cells in Human Pancreatic Cancer

V-domain immunoglobulin suppressor of T-cell activation (VISTA) is constitutively expressed in hematopoietic lineage and is highly up-regulated in tumor infiltrated myeloid cells and regulatory T-cells in animal models. However, its expression in human pancreatic tumor microenvironment remains unknown. In this research, we aimed at the expression of VISTA in human pancreatic cancer samples.

METHODS

We performed immunohistochemistry to determine VISTA expression in human pancreatic cancer samples.

RESULTS

We found that 88.46% of the patients showed high-density infiltration of polymorphonuclear neutrophils and mononuclear immune cells with up-regulated expression of VISTA in cancer tissues, especially in the necrotic foci. Interestingly, it was minimally expressed in pancreatic cancerous cells and was not detectable in either normal ducts or islet cells in cancerous or normal pancreatic tissues.

CONCLUSIONS

We conclude that VISTA is predominantly expressed and up-regulated in the high-density infiltrated immune cells but minimal in human pancreatic cancerous cells. Our results for the first time highlight pancreatic immunosuppressive tumor microenvironment contributed by VISTA and its potential as a prominent target for pancreatic cancer immunotherapy.

A phase I trial of the MEK inhibitor selumetinib (AZD6244) in pediatric patients with recurrent or refractory low-grade glioma: a Pediatric Brain Tumor Consortium (PBTC) study

Background

Activation of the mitogen-activated protein kinase pathway is important for growth of pediatric low-grade gliomas (LGGs). The aim of this study was to determine the recommended phase II dose (RP2D) and the dose-limiting toxicities (DLTs) of the MEK inhibitor selumetinib in children with progressive LGG.

Methods

Selumetinib was administered orally starting at 33 mg/m2/dose b.i.d., using the modified continual reassessment method. Pharmacokinetic analysis was performed during the first course. BRAF aberrations in tumor tissue were determined by real-time polymerase chain reaction and fluorescence in situ hybridization.

Results

Thirty-eight eligible subjects were enrolled. Dose levels 1 and 2 (33 and 43 mg/m2/dose b.i.d.) were excessively toxic. DLTs included grade 3 elevated amylase/lipase (n = 1), headache (n = 1), mucositis (n = 2), and grades 2-3 rash (n = 6). At dose level 0 (25 mg/m2/dose b.i.d, the RP2D), only 3 of 24 subjects experienced DLTs (elevated amylase/lipase, rash, and mucositis). At the R2PD, the median (range) area under the curve (AUC0-∞) and apparent oral clearance of selumetinib were 3855 ng*h/mL (1780 to 7250 ng × h/mL) and 6.5 L × h-1 × m-2 (3.4 to 14.0 L × h-1 × m-2), respectively. Thirteen of 19 tumors had BRAF abnormalities. Among the 5 (20%) of 25 subjects with sustained partial responses, all at the RP2D, 4 had BRAF aberrations, 1 had insufficient tissue. Subjects received a median of 13 cycles (range: 1-26). Fourteen (37%) completed all protocol treatment (26 cycles [n = 13], 13 cycles [n = 1]) with at least stable disease; 2-year progression-free survival at the RP2D was 69 ± SE 9.8%.

Conclusion

Selumetinib has promising antitumor activity in children with LGG. Rash and mucositis were the most common DLTs.

The selective MEK1 inhibitor Selumetinib enhances the antitumor activity of everolimus against renal cell carcinoma in vitro and in vivo

Renal cell carcinoma (RCC) is a urologic malignant cancer and often diagnosed at an advanced stage, which results in high mortality. Targeted therapy may improve the quality of life and survival of patients who are not suitable for nephrectomy. Everolimus, an mTOR inhibitor, is currently used as sequential or second-line therapy for RCC refractory to Sunitinib or sorafenib. However, its efficiency is palliative. In this study, we evaluated whether the antitumor activity of everolimus against RCC is enhanced by Selumetinib, a selective MEK1 inhibitor. We discovered that everolimus in combination with Selumetinib synergistically inhibited the proliferation of Caki-1, 786-O and 769-P cells in vitro. Mechanistically, this combination decreased p-RPS6 and p-4E-BP1 dramatically, which causes G1 cell cycle arrest and prevents reactivation of AKT and ERK. In vivo, the antitumor efficacy and pharmacodynamic biomarkers of the combination therapy were recapitulated in Caki-1 xenograft model. In addition, this combination treatment potently inhibited angiogenesis in xenograft models by impairing VEGF secretion from tumor cells. Our findings provide a sound evidence that combination of everolimus and Selumetinib is a potential dual-targeted strategy for renal cell carcinoma.

Identification of Angiogenesis Inhibitors Using a Co-culture Cell Model in a High-Content and High-Throughput Screening Platform

Angiogenesis is an important hallmark of cancer, contributing to tumor formation and metastasis. In vitro angiogenesis models for analyzing tube formation serve as useful tools to study these processes. However, current in vitro co-culture models using primary cells have limitations in usefulness and consistency. Therefore, in the present study, an in vitro co-culture assay system was optimized in a 1536-well format for high-throughput screening using human telomerase reverse transcriptase (hTERT)–immortalized mesenchymal stem cells and aortic endothelial cells. The National Center for Advancing Translational Sciences (NCATS) Pharmaceutical Collection (NPC) library containing 2816 drugs was evaluated using the in vitro co-culture assay. From the screen, 35 potent inhibitors (IC₅₀ ≤1 µM) were identified, followed by 15 weaker inhibitors (IC₅₀ 1–50 µM). Moreover, many known angiogenesis inhibitors were identified, such as topotecan, docetaxel, and bortezomib. Several potential novel angiogenesis inhibitors were also identified from this study, including thimerosal and podofilox. Among the inhibitors, some compounds were proved to be involved in the hypoxia-inducible factor-1α (HIF-1α) and the nuclear factor-kappa B (NF-κB) pathways. The co-culture model developed by using hTERT-immortalized cell lines described in this report provides a consistent and robust in vitro system for antiangiogenic drug screening.

Genistein decreases A549 cell viability via inhibition of the PI3K/AKT/HIF‑1α/VEGF and NF‑κB/COX‑2 signaling pathways

Genistein is an important chemopreventive agent against atherosclerosis and cancer. However, whether genistein is effective in the treatment of lung cancer, and its underlying mechanism, remains to be determined. The present study demonstrated that genistein treatment of A549 lung cancer cells decreased viability in a dose‑ and time‑dependent manner, and induced apoptosis. Additionally, A549 cells exhibited significantly increased reactive oxygen species formation and cytochrome‑c leakage, and activated caspase‑3, B‑cell lymphoma 2‑associated X protein and apoptosis inducing factor expression levels, which are involved in the mitochondrial apoptosis pathway. Furthermore, the phosphatidylinositol‑4,5‑biphosphate 3‑kinase (PI3K)/protein kinase B (AKT)/hypoxia‑inducible factor‑1α (HIF‑1α) and nuclear factor‑κB (NF‑κB)/cyclooxygenase‑2 (COX‑2) signaling pathways were significantly downregulated by genistein treatment. In conclusion, reduced proliferation and increased apoptosis in A549 lung cancer cells was associated with inhibition of the PI3K/AKT/HIF‑1α/ and NF‑κB/COX‑2 signaling pathways, which implicates genistein as a potential chemotherapeutic agent for the treatment of lung cancer.

Involvement of c-Fos in the Promotion of Cancer Stem-like Cell Properties in Head and Neck Squamous Cell Carcinoma

Purpose: Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. Although improvements in surgical techniques, chemotherapy and radiation delivery, and supportive care have improved quality of life for patients with HNSCC, regional and distant recurrence remain common. Recent evidence suggests that cancer stem-like cells (CSC) play a significant role in recurrence and chemoresistance. We previously observed that c-Fos was highly upregulated in the HNSCC sphere-forming cells. Consequences of c-Fos upregulation for the biology of HNSCC-CSCs are poorly understood. In this study, we investigated the role of c-Fos in renewal of stemness of HNSCC and tumor growth.Experimental Design and Results: We generated stable HNSCC cell lines ectopically expressing the c-Fos gene. Exogenous expression of c-Fos in nontumorigenic MDA1386Tu cells makes these cells tumorigenic in nude mice. Furthermore, subcutaneous transplantation of c-Fos-overexpressing Cal27 cells (tumorigenic) into immunocompromised mice enhanced tumor growth as compared with parental cells. Mechanistic investigations demonstrated that c-Fos overexpression enhanced the epithelial-mesenchymal transition (EMT) state and expression of CSC markers (Nanog, c-Myc, Sox2, and Notch1). Ectopic expression of c-Fos in HNSCC cells also displays increased sphere formation. We further observed that overexpression of c-Fos increased the expression of pERK and cyclin D1 in HNSCC cells.Conclusions: Together, our results strongly suggest a novel role of c-Fos as a regulator of EMT and cancer stem cell reprogramming in HNSCC cells, which may hold potential as a CSC-directed therapeutic approach to improve HNSCC treatment. Clin Cancer Res; 23(12); 3120-8. ©2016 AACR.

CXCR7/p-ERK-Signaling Is a Novel Target for Therapeutic Vasculogenesis in Patients with Coronary Artery Disease

Coronary artery disease (CAD) is characterized by insufficient vasculogenic response to ischemia, which is typically accompanied by dysfunction of endothelial outgrowth cells (EOCs). CXC chemokine receptor 7 (CXCR7) is a key modulator of the neovascularization of EOCs to perfusion defect area. However, the mechanism underlying the role of EOCs in CAD-related abnormal vasculogenesis is still not clear. Here, we investigated the alteration of EOCs-related vasculogenic capacity in patients with CAD and its potential mechanism. Compared with EOCs isolated from healthy subjects, EOCs from CAD patients showed an impaired vasculogenic function in vitro. CXCR7 expression of EOCs from CAD patients was downregulated. Meanwhile, the phosphorylation of extracellular signal-regulated kinase (ERK), downstream of CXCR7 signaling, was also reduced. CXCR7 expression introduced by adenovirus increased the phosphorylation of ERK, which was parallel to improved function of EOCs. The enhanced adhesion and vasculogenesis of EOCs can be blocked by short interfering RNA (siRNA) against CXCR7 and ERK inhibitor PD098059. Therefore, our study demonstrates that the upregulation of CXCR7 signaling contributes to increased vasculogenic capacity of EOCs from CAD patients, indicating that CXCR7 signaling may be a novel therapeutic vasculogenic target for CAD.

The anti-angiogenic effect and novel mechanisms of action of Combretastatin A-4

Combretastatin A-4 (CA4) is the lead compound of a relatively new class of vascular disrupting agents that target existing tumor blood vessels. Recent studies showed the CA4 might inhibit angiogenesis. However, the underlying molecular mechanisms by which CA4 exerts its anti-angiogenic effects are not fully understood. In this study, we revealed that CA4 inhibited vascular endothelial growth factor (VEGF)-induced proliferation, migration and capillary-like tube formation of human umbilical vascular endothelial cells (HUVECs). In in vivo assay, CA4 suppressed neovascularization in chicken chorioallantoic membrane (CAM) model and decreased the microvessel density in tumor tissues of a breast cancer MCF-7 xenograft mouse model. In addition, CA4 decreased the expression level and secretion of VEGF both in MCF-7 cells and HUVECs under hypoxia, as well as the activation of VEGFR-2 and its downstream signaling mediators following VEGF stimulation in HUVECs. Moreover, VEGF and VEGFR-2 expression in tumor tissues of the mouse xenograft model were down-regulated following CA4 treatment. Taken together, results from the current work provide clear evidence that CA4 functions in endothelial cell system to inhibit angiogenesis, at least in part, by attenuating VEGF/VEGFR-2 signaling pathway.